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QOJ

IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#73937#5443. Security at Museumsyuto1115WA 2ms3364kbC++1717.5kb2023-01-29 17:21:302023-01-29 17:21:31

Judging History

你现在查看的是最新测评结果

  • [2023-08-10 23:21:45]
  • System Update: QOJ starts to keep a history of the judgings of all the submissions.
  • [2023-01-29 17:21:31]
  • 评测
  • 测评结果:WA
  • 用时:2ms
  • 内存:3364kb
  • [2023-01-29 17:21:30]
  • 提交

answer

#include<bits/stdc++.h>
#include<ext/pb_ds/assoc_container.hpp>
#include<ext/pb_ds/tree_policy.hpp>
#include<ext/pb_ds/tag_and_trait.hpp>
#define overload4(_1, _2, _3, _4, name, ...) name
#define rep1(i, n) for (ll i = 0; i < ll(n); ++i)
#define rep2(i, s, n) for (ll i = ll(s); i < ll(n); ++i)
#define rep3(i, s, n, d) for(ll i = ll(s); i < ll(n); i+=d)
#define rep(...) overload4(__VA_ARGS__,rep3,rep2,rep1)(__VA_ARGS__)
#define rrep1(i, n) for (ll i = ll(n)-1; i >= 0; i--)
#define rrep2(i, n, t) for (ll i = ll(n)-1; i >= (ll)t; i--)
#define rrep3(i, n, t, d) for (ll i = ll(n)-1; i >= (ll)t; i-=d)
#define rrep(...) overload4(__VA_ARGS__,rrep3,rrep2,rrep1)(__VA_ARGS__)
#define all(a) a.begin(),a.end()
#define rall(a) a.rbegin(),a.rend()
#define SUM(a) accumulate(all(a),0LL)
#define MIN(a) *min_element(all(a))
#define MAX(a) *max_element(all(a))
#define SORT(a) sort(all(a));
#define REV(a) reverse(all(a));
#define SZ(a) int(a.size())
#define popcount(x) __builtin_popcountll(x)
#define pf push_front
#define pb push_back
#define ef emplace_front
#define eb emplace_back
#define ppf pop_front
#define ppb pop_back
#ifdef __LOCAL
#define debug(...) { cout << #__VA_ARGS__; cout << ": "; print(__VA_ARGS__); cout << flush; }
#else
#define debug(...) void(0);
#endif
#define INT(...) int __VA_ARGS__;scan(__VA_ARGS__)
#define LL(...) ll __VA_ARGS__;scan(__VA_ARGS__)
#define STR(...) string __VA_ARGS__;scan(__VA_ARGS__)
#define CHR(...) char __VA_ARGS__;scan(__VA_ARGS__)
#define DBL(...) double __VA_ARGS__;scan(__VA_ARGS__)
#define LD(...) ld __VA_ARGS__;scan(__VA_ARGS__)
using namespace std;
using namespace __gnu_pbds;
using ll = long long;
using ld = long double;
using P = pair<int, int>;
using LP = pair<ll, ll>;
using vi = vector<int>;
using vvi = vector<vi>;
using vvvi = vector<vvi>;
using vl = vector<ll>;
using vvl = vector<vl>;
using vvvl = vector<vvl>;
using vd = vector<double>;
using vvd = vector<vd>;
using vs = vector<string>;
using vc = vector<char>;
using vvc = vector<vc>;
using vb = vector<bool>;
using vvb = vector<vb>;
using vp = vector<P>;
using vvp = vector<vp>;
using vlp = vector<LP>;
using vvlp = vector<vlp>;
template<class T>
using PQ = priority_queue<T>;
template<class T>
using PQrev = priority_queue<T, vector<T>, greater<T>>;

template<class S, class T>
istream &operator>>(istream &is, pair<S, T> &p) { return is >> p.first >> p.second; }

template<class S, class T>
ostream &operator<<(ostream &os, const pair<S, T> &p) { return os << '{' << p.first << ", " << p.second << '}'; }

template<class S, class T, class U>
istream &operator>>(istream &is, tuple<S, T, U> &t) { return is >> get<0>(t) >> get<1>(t) >> get<2>(t); }

template<class S, class T, class U>
ostream &operator<<(ostream &os, const tuple<S, T, U> &t) {
    return os << '{' << get<0>(t) << ", " << get<1>(t) << ", " << get<2>(t) << '}';
}

template<class T>
istream &operator>>(istream &is, vector<T> &v) {
    for (T &t: v) { is >> t; }
    return is;
}

template<class T>
ostream &operator<<(ostream &os, const vector<T> &v) {
    os << '[';
    rep(i, v.size()) os << v[i] << (i == int(v.size() - 1) ? "" : ", ");
    return os << ']';
}

template<class T>
ostream &operator<<(ostream &os, const deque<T> &v) {
    os << '[';
    rep(i, v.size()) os << v[i] << (i == int(v.size() - 1) ? "" : ", ");
    return os << ']';
}

template<class T>
ostream &operator<<(ostream &os, const set<T> &st) {
    os << '{';
    auto it = st.begin();
    while (it != st.end()) {
        os << (it == st.begin() ? "" : ", ") << *it;
        it++;
    }
    return os << '}';
}

template<class T>
ostream &operator<<(ostream &os, const multiset<T> &st) {
    os << '{';
    auto it = st.begin();
    while (it != st.end()) {
        os << (it == st.begin() ? "" : ", ") << *it;
        it++;
    }
    return os << '}';
}

template<class T, class U>
ostream &operator<<(ostream &os, const map<T, U> &mp) {
    os << '{';
    auto it = mp.begin();
    while (it != mp.end()) {
        os << (it == mp.begin() ? "" : ", ") << *it;
        it++;
    }
    return os << '}';
}

template<class T>
void vecout(const vector<T> &v, char div = '\n') {
    rep(i, v.size()) cout << v[i] << (i == int(v.size() - 1) ? '\n' : div);
}

template<class T>
bool constexpr chmin(T &a, T b) {
    if (a > b) {
        a = b;
        return true;
    }
    return false;
}

template<class T>
bool constexpr chmax(T &a, T b) {
    if (a < b) {
        a = b;
        return true;
    }
    return false;
}

void scan() {}

template<class Head, class... Tail>
void scan(Head &head, Tail &... tail) {
    cin >> head;
    scan(tail...);
}

template<class T>
void print(const T &t) { cout << t << '\n'; }

template<class Head, class... Tail>
void print(const Head &head, const Tail &... tail) {
    cout << head << ' ';
    print(tail...);
}

template<class... T>
void fin(const T &... a) {
    print(a...);
    exit(0);
}

template<class T>
vector<T> &operator+=(vector<T> &v, T x) {
    for (T &t: v) t += x;
    return v;
}

template<class T>
vector<T> &operator-=(vector<T> &v, T x) {
    for (T &t: v) t -= x;
    return v;
}

template<class T>
vector<T> &operator*=(vector<T> &v, T x) {
    for (T &t: v) t *= x;
    return v;
}

template<class T>
vector<T> &operator/=(vector<T> &v, T x) {
    for (T &t: v) t /= x;
    return v;
}

struct Init_io {
    Init_io() {
        ios::sync_with_stdio(false);
        cin.tie(nullptr);
        cout.tie(nullptr);
        cout << boolalpha << fixed << setprecision(15);
        cerr << boolalpha << fixed << setprecision(15);
    }
} init_io;

const string yes[] = {"no", "yes"};
const string Yes[] = {"No", "Yes"};
const string YES[] = {"NO", "YES"};
const int inf = 1001001001;
const ll linf = 1001001001001001001;

void rearrange(const vi &) {}

template<class T, class... Tail>
void rearrange(const vi &ord, vector<T> &head, Tail &...tail) {
    assert(ord.size() == head.size());
    vector<T> ori = head;
    rep(i, ord.size()) head[i] = ori[ord[i]];
    rearrange(ord, tail...);
}

template<class T, class... Tail>
void sort_by(vector<T> &head, Tail &... tail) {
    vi ord(head.size());
    iota(all(ord), 0);
    sort(all(ord), [&](int i, int j) { return head[i] < head[j]; });
    rearrange(ord, head, tail...);
}

bool in_rect(int i, int j, int h, int w) {
    return 0 <= i and i < h and 0 <= j and j < w;
}

template<class T, class S>
vector<T> cumsum(const vector<S> &v, bool shift_one = true) {
    int n = v.size();
    vector<T> res;
    if (shift_one) {
        res.resize(n + 1);
        rep(i, n) res[i + 1] = res[i] + v[i];
    } else {
        res.resize(n);
        if (n) {
            res[0] = v[0];
            rep(i, 1, n) res[i] = res[i - 1] + v[i];
        }
    }
    return res;
}

vvi graph(int n, int m, bool directed = false, int origin = 1) {
    vvi G(n);
    rep(_, m) {
        INT(u, v);
        u -= origin, v -= origin;
        G[u].pb(v);
        if (!directed) G[v].pb(u);
    }
    return G;
}

template<class T>
vector<vector<pair<int, T>>> weighted_graph(int n, int m, bool directed = false, int origin = 1) {
    vector<vector<pair<int, T>>> G(n);
    rep(_, m) {
        int u, v;
        T w;
        scan(u, v, w);
        u -= origin, v -= origin;
        G[u].eb(v, w);
        if (!directed) G[v].eb(u, w);
    }
    return G;
}

template<int mod>
class modint {
    ll x;
public:
    constexpr modint(ll x = 0) : x((x % mod + mod) % mod) {}
    
    static constexpr int get_mod() { return mod; }
    
    constexpr int val() const { return x; }
    
    constexpr modint operator-() const { return modint(-x); }
    
    constexpr modint &operator+=(const modint &a) {
        if ((x += a.val()) >= mod) x -= mod;
        return *this;
    }
    
    constexpr modint &operator++() { return *this += 1; }
    
    constexpr modint &operator-=(const modint &a) {
        if ((x += mod - a.val()) >= mod) x -= mod;
        return *this;
    }
    
    constexpr modint &operator--() { return *this -= 1; }
    
    constexpr modint &operator*=(const modint &a) {
        (x *= a.val()) %= mod;
        return *this;
    }
    
    constexpr modint operator+(const modint &a) const {
        modint res(*this);
        return res += a;
    }
    
    constexpr modint operator-(const modint &a) const {
        modint res(*this);
        return res -= a;
    }
    
    constexpr modint operator*(const modint &a) const {
        modint res(*this);
        return res *= a;
    }
    
    constexpr modint pow(ll t) const {
        modint res = 1, a(*this);
        while (t > 0) {
            if (t & 1) res *= a;
            t >>= 1;
            a *= a;
        }
        return res;
    }
    
    template<int m>
    friend istream &operator>>(istream &, modint<m> &);
    
    // for prime mod
    constexpr modint inv() const { return pow(mod - 2); }
    
    constexpr modint &operator/=(const modint &a) { return *this *= a.inv(); }
    
    constexpr modint operator/(const modint &a) const {
        modint res(*this);
        return res /= a;
    }
    
    // constraints : mod = 2 or val = 0 or val^((mod-1)/2) ≡ 1
    //               mod is prime
    // time complexity : O(log^2 p)
    // reference : https://nyaannyaan.github.io/library/modulo/mod-sqrt.hpp
    modint sqrt() const {
        if (x < 2) return x;
        assert(this->pow((mod - 1) >> 1).val() == 1);
        modint b = 1;
        while (b.pow((mod - 1) >> 1).val() == 1) b += 1;
        ll m = mod - 1, e = 0;
        while (~m & 1) m >>= 1, e += 1;
        modint X = this->pow((m - 1) >> 1);
        modint Y = (*this) * X * X;
        X *= *this;
        modint Z = b.pow(m);
        while (Y.val() != 1) {
            ll j = 0;
            modint t = Y;
            while (t.val() != 1) {
                j += 1;
                t *= t;
            }
            Z = Z.pow(1LL << (e - j - 1));
            X *= Z;
            Z *= Z;
            Y *= Z;
            e = j;
        }
        return X;
    }
};

using modint998244353 = modint<998244353>;
using modint1000000007 = modint<1000000007>;

template<int mod>
istream &operator>>(istream &is, modint<mod> &a) {
    ll x;
    is >> x;
    a = modint<mod>(x);
    return is;
}

template<int mod>
constexpr ostream &operator<<(ostream &os, const modint<mod> &a) { return os << a.val(); }

template<int mod>
constexpr bool operator==(const modint<mod> &a, const modint<mod> &b) { return a.val() == b.val(); }

template<int mod>
constexpr bool operator!=(const modint<mod> &a, const modint<mod> &b) { return a.val() != b.val(); }

template<int mod>
constexpr modint<mod> &operator++(modint<mod> &a) { return a += 1; }

template<int mod>
constexpr modint<mod> &operator--(modint<mod> &a) { return a -= 1; }

using mint = modint998244353;

using vm = vector<mint>;
using vvm = vector<vm>;

using point = LP;

ll cross(const point &a, const point &b) {
    return a.first * b.second - a.second * b.first;
}

ll dot(const point &a, const point &b) {
    return a.first * b.first + a.second * b.second;
}

ll norm(const point &p) {
    return p.first * p.first + p.second * p.second;
}

int sgn(ll l) {
    if (l < 0) return -1;
    if (l == 0) return 0;
    return 1;
}

int ccw(const point &a, const point &b, const point &c) {
    // 1 -> c is upper than line(a,b)
    // -1 -> c is lower than line(a,b)
    // 2 -> in order [a,b,c]
    // -2 -> in order [c,a,b]
    // 0 -> in order [a,c,b]
    point nb = {b.first - a.first, b.second - a.second};
    point nc = {c.first - a.first, c.second - a.second};
    if (sgn(cross(nb, nc))) return sgn(cross(nb, nc));
    if (sgn(dot(nb, nc)) < 0) return -2;
    if (sgn(norm(nc) - norm(nb)) > 0) return 2;
    return 0;
}

struct segment {
    point a, b;
    
    segment(point a = point(), point b = point()) : a(a), b(b) {}
    
    bool online(const point &p) const { return !ccw(a, b, p); }
};

ostream &operator<<(ostream &os, const segment &l) { return os << '{' << l.a << ',' << l.b << '}'; }

bool intersect(const segment &l, const segment &m) {
    return ccw(l.a, l.b, m.a) * ccw(l.a, l.b, m.b) <= 0 &&
           ccw(m.a, m.b, l.a) * ccw(m.a, m.b, l.b) <= 0;
}

// [-pi, pi)
// no (0, 0)
bool arg_cmp(const LP &a, const LP &b) {
    int ua = a.second > 0 or (a.second == 0 and a.first > 0);
    int ub = b.second > 0 or (b.second == 0 and b.first > 0);
    if (ua == ub) {
        ll cross = a.first * b.second - a.second * b.first;
        return cross > 0;
    } else {
        return ua < ub;
    }
}

class binomial_coefficient {
public:
    vector<mint> fact, ifact;
    
    binomial_coefficient(int n) : fact(n + 1), ifact(n + 1) {
        fact[0] = 1;
        for (int i = 1; i <= n; ++i) fact[i] = fact[i - 1] * i;
        ifact[n] = fact[n].inv();
        for (int i = n; i >= 1; --i) ifact[i - 1] = ifact[i] * i;
    }
    
    mint operator()(int n, int k) {
        if (k < 0 || k > n) return 0;
        return fact[n] * ifact[k] * ifact[n - k];
    }
    
    mint P(int n, int k) {
        if (k < 0 || k > n) return 0;
        return fact[n] * ifact[n - k];
    }
    
    mint naive(mint n, int k) {
        mint res = 1;
        rep(i, k) {
            res *= n - i;
            res /= i + 1;
        }
        return res;
    }
    
    mint naive_P(mint n, int k) {
        mint res = 1;
        rep(i, k) {
            res *= n - i;
        }
        return res;
    }
} binom(1000);

int main() {
    INT(n);
    vl x(n), y(n);
    rep(i, n) scan(x[i], y[i]);
    vector<point> pt(n);
    rep(i, n) pt[i] = {x[i], y[i]};
    vvi dir(n, vi(n, -1));
    {
        vector<tuple<int, int, LP>> tmp;
        rep(i, n) rep(j, n) {
                if (i == j) continue;
                tmp.eb(i, j, LP{x[j] - x[i], y[j] - y[i]});
            }
        sort(all(tmp), [](auto a, auto b) { return arg_cmp(get<2>(a), get<2>(b)); });
        int now = -1;
        rep(i, SZ(tmp)) {
            if (i == 0 or arg_cmp(get<2>(tmp[i - 1]), get<2>(tmp[i]))) ++now;
            dir[get<0>(tmp[i])][get<1>(tmp[i])] = now;
        }
    }
    debug(dir);
    // is k in [i,j](ccw)?
    auto in_int = [](int i, int j, int k) {
        if (i <= j) return i <= k and k <= j;
        else return i <= k or k <= j;
    };
    vvi ok(n, vi(n, true));
    rep(i, n) rep(j, i + 1, n) {
            rep(_, 2) {
                int a = (i + n - 1) % n;
                int b = (i + 1) % n;
                ok[i][j] &= in_int(dir[i][b], dir[i][a], dir[i][j]);
                swap(i, j);
            }
            segment s(pt[i], pt[j]);
            rep(k, n) {
                int a = k;
                int b = (k + 1) % n;
                if (s.online(pt[a])) continue;
                if (s.online(pt[b])) continue;
                segment t(pt[a], pt[b]);
                ok[i][j] &= !intersect(s, t);
            }
            rep(k, n) {
                if (i == k or j == k) continue;
                if (!s.online(pt[k])) continue;
                int a = (k + n - 1) % n;
                int b = (k + 1) % n;
                ok[i][j] &= in_int(dir[k][b], dir[k][a], dir[k][i]);
                ok[i][j] &= in_int(dir[k][b], dir[k][a], dir[k][j]);
            }
            ok[i][j] = ok[j][i] = (ok[i][j] & ok[j][i]);
        }
    mint ans;
    auto convex_low = [&](int s) -> vm {
        vp eg;
        rep(i, n) rep(j, n) if (i != j) {
                    if (!ok[i][j]) continue;
                    if (!arg_cmp({0, -1}, {x[j] - x[i], y[j] - y[i]})) continue;
                    if (arg_cmp({0, 1}, {x[j] - x[i], y[j] - y[i]})) continue;
                    eg.eb(i, j);
                }
        sort(all(eg),
             [&](P a, P b) {
                 auto [ai, aj] = a;
                 auto [bi, bj] = b;
                 if (dir[ai][aj] != dir[bi][bj]) return dir[ai][aj] < dir[bi][bj];
                 return pt[ai] < pt[aj];
             });
        vm dp(n);
        dp[s] = 1;
        for (auto [i, j]: eg) {
            dp[j] += dp[i];
        }
        return dp;
    };
    auto convex_up = [&](int s) -> vm {
        vp eg;
        rep(i, n) rep(j, n) if (i != j) {
                    if (!ok[i][j]) continue;
                    if (!arg_cmp({0, -1}, {x[j] - x[i], y[j] - y[i]})) continue;
                    if (arg_cmp({0, 1}, {x[j] - x[i], y[j] - y[i]})) continue;
                    eg.eb(i, j);
                }
        sort(all(eg),
             [&](P a, P b) {
                 auto [ai, aj] = a;
                 auto [bi, bj] = b;
                 if (dir[ai][aj] != dir[bi][bj]) return dir[ai][aj] > dir[bi][bj];
                 return pt[ai] < pt[aj];
             });
        vm dp(n);
        dp[s] = 1;
        for (auto [i, j]: eg) {
            dp[j] += dp[i];
        }
        return dp;
    };
    rep(s, n) {
        vm dpl = convex_low(s);
        vm dpu = convex_up(s);
        debug(s);
        debug(dpl);
        debug(dpu);
        rep(t, n) {
            if (s == t) continue;
            ans += dpl[t] * dpu[t];
        }
    }
    rep(s, n) rep(t, s + 1, n) {
            if (!ok[s][t]) continue;
            int cnt = 0;
            rep(i, n) {
                if (i == s or i == t) continue;
                if (segment(pt[s], pt[t]).online(pt[i])) ++cnt;
            }
            ans -= mint(4).pow(cnt);
            ans += mint(2).pow(cnt);
        }
    fin(ans);
}

Details

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Test #1:

score: 0
Wrong Answer
time: 2ms
memory: 3364kb

input:

7
0 20
40 0
40 20
70 50
50 70
30 50
0 50

output:

45

result:

wrong answer 1st numbers differ - expected: '56', found: '45'